Instructions for preparing seeds and soil for planting Thai jackfruit

Thai jackfruit is popular because it bears fruit quickly and is easy to care for. However, choosing the wrong variety and preparing the soil from the beginning will lead to many problems 5-10 years later. Instructions for deciding on land, choosing varieties and creating motifs for the Mekong Delta growing region.

Summary: Thai jackfruit (Changai variety) bears fruit quickly, has high yield, and has a stable market. But unsuitable soil or unknown varieties will affect the tree's entire life cycle of 20-25 years. This article guides three pre-sowing decisions — soil assessment, variety selection, and motif placement — that determine about 70 percent of a orchard's success.

Applies to: New or renovated jackfruit orchards, Mekong Delta (Tien Giang, Vinh Long, Dong Thap, Hau Giang, An Giang) and Southeast (Dong Nai, Binh Phuoc).

Duration: Prepare 3-6 months before planting. Plant at the beginning of the rainy season.

Difficulty level: Medium.

Estimated additional costs: 40-80 million VND per hectare for land improvement and seedlings.

Evaluate the soil before deciding to plant jackfruit

Jackfruit is an easy-going fruit tree, but not all soil types are suitable. Before investing, check three factors:

Elevation and drainage

• Jackfruit is more tolerant of humidity than durian but cannot tolerate prolonged flooding. Soil submerged more than 30 centimeters deep for more than 7-10 days will suffocate the roots.
• The land must be at least 50 centimeters higher than the highest water level of the year (or up to this height).
• Deeply flooded areas in the flood season need a mop 80-100 centimeters high.

Soil properties

• pH KCl 5.5-6.5 is the optimal range. Acidic soil below 5.0 needs to be amended with lime.
• The soil is loose and has good air circulation. If clay soil is too heavy, it traps air and roots develop poorly.
• Organic content above 2 percent is best. Soils that are poor in organic matter need to be fertilized before planting.
• Avoid heavily alkaline soils (pH below 4.5 and high sulfate), permanently saline soils, and rubber-grown soils with a history of nematodes.

Source of irrigation water

• Ensure there is a water source for irrigation in the dry season — wells, ponds, in-field canals.
• Coastal areas need to measure water salinity. Jackfruit can tolerate light salinity below 1 part per thousand, but cannot tolerate salinity above 2 parts per thousand.

Take soil samples for analysis before deciding to plant. Cost 1-2 million VND for analysis of pH, organic matter, phosphorus, potassium, calcium-magnesium, nematodes. Small investments save big risks.

Choose a jackfruit variety

Popular Thai jackfruit variety

• Changai Thai jackfruit: most popular today. The fruit weighs 8-15 kilograms, has yellow segments, thick flesh, and is moderately sweet. Produces fruit 2.5-3 years after planting.
• Early Thai Sieu jackfruit: bears fruit after 18-24 months. Fruits are smaller than 5-10 kilograms.
• Red-fleshed jackfruit: 4-8 kg fruit, characteristic red rice. Niche market with higher price.

Quick comparison:

Seed source

• Buy from a nursery certified by the Department of Agriculture or a provincial seed center.
• Seedlings must have:
• Age 10-15 months from transplant.
• Height 50-80 centimeters from the bulb surface.
• Stem diameter on rootstock is 0.8-1.2 centimeters.
• The grafted eyes are good, no cracks.
• Old leaves are stable, no pests.
• The roots in the pot are strong, no twisted roots.

Avoid:

• The seedling is too old, more than 18 months old — the roots in the pot are tight, and after planting, they develop poorly.
• Seedlings are too young under 8 months — weak, low survival rate.
• Plants grown from seeds — not recommended. Jackfruit seeds bear fruit 5-7 years late and are unstable.

Distribution of varieties in the orchard

• orchards under 1 hectare: only grow one main variety.
• 1-3 hectare orchard: 70-80 percent main varieties + 20-30 percent secondary varieties. There are cross-pollination benefits and reduced market risk.
• orchard over 3 hectares: consider 2-3 varieties to diversify harvest according to time.

Make a motif and arrange the orchard

Motif size

• Round molipe: diameter 1-1.2 meters, height 50-80 centimeters (lightly flooded area).
• Long Molip: 1-1.5 meters wide, 60-100 centimeters high, arbitrary length.
• Deep flooded area reaches 100-120 centimeters high.

Cover the tissue with organic-rich topsoil. Do not use nutrient-poor clay from deep layers.

Planting density

• Changai Thai jackfruit: 8 meters × 8 meters (156 trees per hectare) or 7 × 9 meters (158 trees).
• Thai Sieu jackfruit small canopy: 6 × 7 meters (238 trees) or 6 × 6 (278 trees).
• Red jackfruit: 7 × 8 meters (179 trees).

Avoid planting too thickly — after 7-10 years the canopy overlaps, productivity decreases.

Direction and design

• The rows of trees face East — West for optimal light.
• Drainage ditch between rows — 50-80 centimeters deep, 40-60 centimeters wide.
• The path is 3-4 meters wide for vehicles to enter.
• In areas with strong winds: plant windbreaks around the perimeter of the orchard (such as rice plants, acacia leaves).

Improve soil before planting

Primer

In each planting hole (diameter 60 centimeters, depth 40 centimeters), fertilize:

• 15-25 kilograms of decomposed manure or compost (compost).
• 0.5-1 kilogram of lime (amend pH if soil is acidic).
• 200-300 grams of fused phosphate.
• 100-150 grams of *N-P-K* 16-16-8 fertilizer.

Mix well with topsoil. Leave for 15-30 days before planting — soil microorganisms are active, fertilizer does not shock young plant roots.

Lime amendment for acidic soil

• pH below 5.5: apply 1.5-2 tons of lime per hectare, spread evenly on the mop surface, and plow.
• pH 5.5-6.0: apply 0.8-1 ton of lime per hectare.
• pH above 6.5: no need to apply lime.

Apply lime 30-60 days before planting so that the lime dissolves evenly and the pH is stable.

Planting trees and taking care of them for the first 6 months

Plant

• Plant at the beginning of the rainy season (May-June in the Mekong Delta).
• Place the tree so that the root collar is 5-10 centimeters above the tissue surface — most important.
• Place a stake to keep the tree straight. Leaning trees will affect canopy structure forever.
• Irrigate immediately after planting — 10-15 liters per tree.

The first month after planting

• Water 5-10 liters per plant every 2-3 days.
• Cover the base with straw and dry grass — retain moisture and limit weeds.
• Temporarily shade 30-40 percent if planted at the beginning of the rainy season with strong sunny days.
• Check weekly — leaning trees, dead trees, worms biting the tops.

February-June

• Light fertilizer: *N-P-K* 16-16-8 at a dose of 50-100 grams per tree, every 30-45 days.
• Cut excess shoots, keeping one main stem.
• Target survival rate over 95 percent. Replant immediately if there are dead trees.

Common mistakes

Growing jackfruit on long-term flooded land: a few years later, trees die en masse due to root disease.

Buy seeds from unknown sources: floating seedlings may be diseased, or the seed is not pure.

Skip soil analysis: planted in acidic or acidic soil, the plant will not grow.

Low mountain slopes: Slightly flooded areas also damage roots in the rainy season.

Planting too thickly to "increase initial yield": after 7-10 years of intercropping, total yield decreases.

Take notes

• Soil analysis results.
• Purchasing source + quantity + price.
• Planting date for each plot.
• Land improvement materials.
• Survival rate after 1 month, 3 months, 6 months.
• The disease occurs in the first 6 months.

References

• *Technical process of planting and caring for jackfruit* — Southern Fruit Institute, 2022.
• *Production of jackfruit for export* — Department of Crop Production, 2023.

Related articles

• Instructions for productive jackfruit care
• Prevention of black fiber phenomenon on jackfruit
• Prevention of fruit borers for jackfruit
• Calculate fertilization recommendations